Blasting-plug.



F. A. GOODROW & E. P. GOODING.

BLASTING PLUG.

APPLIOATIUN FILED JUNI: e. 1910.

' 971,264. Patented Sept. 27, 1910.

FRANK A. eoonaow ANDEDWARD r. eooDINe, or ELGIN, ILLINOIS.

BLvASTING-PLUG.

Specication of Letters atent. I Patented Sept. 27, 1910.

Application led June 6, 1910. Serial No. 565,206.

To all whom it may concern:

Be it known that We, FRANK A. GooDRow and EDWARD F. GooDiNe, both citizens of Illinois, have invented certain new and useful Improvements in Blasting-Plugs, of which the followin is a specification.

At the present time, it is customary, in blasting operations, to close the hole into which the blasting charge has been placed, by means of clay, sand, .mud, stones or other convenient debris, allowing the fuse to project out through said closure. There area number of very serious objections to closing the blast-ing hole in this manner, among which is that the fuse is oft'en injured in the closing operation, and the closure is not as dry as desired; but above all the closure is not as secure and gas-tight as it should be. Very often these closures are blown out of the'hole when the explosion takes place and serious injury has followed such an accident. This is because the direction of the explosive force depends largely upon the resistance to be overcome, and'when a closure blows out the explosive forces may be exerted in a direction wholly unexpected. The effectiveness of the explosion is largely determined bythe amount of gas pressure which may be generated in the charge chamber. It is evident that the greater the security of thevclosure the greater will be the gas pressure generated, and therefore the greater the eiliciency of the explosion.

The objects of this invention are, to pro vide a blasting plug which may be easily placed in the hole after the charge has been located; to provide a blasting plug which shall securely resist blowing out; one which shall have the highest eiiciency in holding up the gas pressure by preventing leakage; one which may be placed wit-hout danger of injuring the fuse; one which may be cheaply manufactured; one which` may be made in standard sizes; and one which shall comprise the fewest possible number of 'parts and shall be of small weight.

Other objects and features will appear from a detailed description of the invention,

which consists in the features of construction and combination of parts hereinafter described and claimed.

In the drawing, Figure 1 is a longitudinal section of the blasting chamber, vshowing a charge of explosive laid in position, the cxlosion chamber being closed by one of our improved blasting plugs, and the fuse projecting through said plug; Fig. 2 is a detailed longitudinal section ofV one of the imf proved plugs, located in the hole and showinglin dotted lines, the manner in which the plug acts to jam the segments out against the sides of the hole when the blast pressure is created; Fig. 3 is a detailed cross section, taken on line 3-3 0f Fig. 2, looking in the direction of the arrows; Fig. 4 is a detailed cross section, similar to Fig. 3, the segments being in expanded position, such as they would occupy when the plug was forced outward by the explosion; Fig. 5 is a side view of the plug; and Fig. 6 is a side view of one of the segments, showing the groove into which may be placed the rubber band or other securing means used for loosely holding the segments linposition around the plug.

Referring to the figures, the device comprlseso a plug7, having an annular body portion 8 of tapered formation, the body portion being provided with forward and rear end flanges 9 and 10 respectively, and with a fuse hole 11. l This body portion may be of brass or cast iron, or any other suitable metal or material. Between the end flanges 9 and 10, we provide a plurality` of annular segments 12 of a'shap'e and size to fit around the tapered portion 8. These segments are of such size and shape that when pushed down adjacent to the flange 9 at the small en'd of the tapered body 8 they will set-together in the manner shown in Fig. 3,

but so that when shoved up toward the flange 10 onto vthe larger portion of the tapered body 8 they will occupy a position'- similarto that shown in Fig. 4:. Evidently these segments will be expanded or contracted in the same-manner if they are held stationary and the plug 8 is moved. These segments may be provided in their outer faces 13 with grooves 14, so located that when the segments are set together on the tapered portion 8 these grooves may aline, so that a rubber band 15' or other ieXible retaining material may be used to hold them in proper position around the body portion.

In Fig. 1, the blasting charge is shown at 16 as located in a hole 17 drilled in the rock 18. The blasting charge 16 is provided with a fuse 19, which may pass throu h the hole 11 of the plug to the exterior o the blasting chamber.

Referring to Fig. 2, it is seen that when a force is applied 1n the direction of the ar rows 20 the tapered plug 8 will be forced out, while the segment 21, which lies against v the bottom of the hole, will be held back by the friction on the hole. This segment will also act to hold the 'other segments back, by reason of the flexible manner in which they are held together, as by the rubber band. When the tapered plug has been thus forced out a certain amount, the several segments will be expanded enough to bring them all into contact with the sidesr of the hole, and thereafter ,they will jam tighter the greater the force exerted on the plug 8. In other Words, when the explosion takes place a blow will be delivered against the inner end of the plug 8, which will thereupon be driven outl until the segments have'been forced into contact with the wall of the hole around its entire periphery, and thereafter an increase vof the blast pressure will merely serve to tighten the Aplug more and more, thus securely resisting blowing out 'and largely preventing leakage of gas.

In order to insure greater reliability of action, the segments should be of a width such that they will hold the body portion of the plug up' high enough so that the flanges 9 and 10 do not strike the lower side of the segments ywill be-'held back while the plug is driven forward. i However, in any case,

if the band 15 is sufficiently flexible, the

spo

lower segment 21 will lie on the bottom of the hole, thus insuring that it will have sufcient friction to hold back while the plug is driven forward. Evidently the exact taper of the plug 8 may be adjusted to. give the most satisfactory results, depending upon the friction between the se ents and the sides of the hole and the relative friction between the materials ofthe plug and .the segments. Also -the number of segments used will depend largely upon the sizeof the blasting hole. v

In operation it is evident that the charge 16 may be inserted in the hole and then the plug 8, with the segments surrounding it, may be inserted over the fuse, which will project out throughthe hole 11. When pressing the blastlng lug' back into the hole, such pressure wil be exerted on the end ofthe plug having the small taper. Therefore the segments will not jam, for the will be held back against the flange 9, an the lug can be easily inserted any -required dlstance by merely pressing against its outer end. I

It is feund that a blastin plug of this type is remarkably efficient 1n service, fory f all viated, for the reason that the greater the practically the only leakage of gas which can occur will be through the fuse hole 11 and Y,a sli ht amount last the'segments 12. Also anger of b owing 'out the plug 'is obexplosive pressure the greater will be the gnp of the plulg1 on the hole. It is evident that a lblast w l drive out thelplug 8 so quickly that the segments will not be moved appreciably, thus insuring that the above described lookin action shall occur. In other words, `it 1s not even Vnecessary that the segments should be originally in frictional contact with the sides of the hole, although this is preferable.

l. In a device of the class described, a tapered body plug, and a plurality of'segmental sections of equal width and of a form to encircle the tapered body ortion, and together present a substantia ly circular periphery, `the tapered body portion being provided Iwith a longitudinal fuse hole, and being further provided with end flanges, and means for retaining the segmental sections in position around the tapered body portion, substantially as described.

2. In a device of the class described, a

body portion comprising -a tapered plug provided with substantially 'circular for-V ward and rear end flanges, and provided with a longitudinal fuse hole, anda plurality of segmental sections of a form to contact the wedge-shaped body portion and together present a substantially circular periphery, the diameter of the forward and rear end flanges being substantially less than the diameter of the segmental sections when 'at the smaller end of the taperedplug portion, whereby when the device is placed in a hole with the segmental sections at the smaller end of the body portion the end flanges may not contact the lower wall of the hole, substantially as described. l

3. In a device of the class described, a body portion comprising a tapered conical plug provided with a longitudinal fuse hole and with forward and rear end flanges ofv substantially circular cross section, and a plurality of segmental sections of 'equal width adapted to encircle the ta ered plug and together present a substantia ly circular peripheral surface substantially parallel to 

